As this type of power output apparatus, there is well-known a conventional power output apparatus including an internal combustion engine, two motors, a so-called Ravigneaux-type planetary gear mechanism, and a parallel-shaft type transmission that can selectively connect two output elements of the planetary gear mechanism with an output member (See Patent Document 1, for example). Also, there is well-known a conventional power output apparatus including a planetary gear mechanism having an input element connected with the internal combustion engine and two output elements respectively connected with a corresponding motor, and a parallel-shaft type transmission having two counter shaft that is connected with the corresponding output elements of the planetary gear mechanism and is linked with a output shaft (See Patent Document 2, for example). In these power output apparatus, the output elements of the planetary gear mechanism can be selectively connected with the output member or the output shaft by the parallel-shaft type transmission. Further, there is well-known a conventional power output apparatus including a power distribution mechanism having an input element connected with an internal combustion engine, a reactive force element connected with a first motor generator, and an output element connected with a second motor generator, and two clutches selectively connecting an axle or an output member with the output element or the reactive force element of the power distribution mechanism (see Patent Document 3, for example).                [Patent Document 1] Japanese Patent Laid-Open No. 2005-155891        [Patent Document 2] Japanese Patent Laid-Open No. 2003-106389        [Patent Document 3] Japanese Patent Laid-Open No. 2005-125876        